Traditional rectifiers generally comprise one or more discrete diodes. These discrete diodes have a junction between materials with specifically designed electrical properties such that at the junction of the materials current can only pass in one direction. The amount of current these diodes are able to pass is proportional to the surface area of this junction.
These diodes are often formed in a semiconductor substrate, sometimes called a die. The die is doped with various materials which augment the electrical properties of various portions of the die in order to form the junction. These doping materials are generally communicated to the die directly through its surface. The less surface area a diode takes up on the die, the more diodes can fit on a die, the higher the semiconductor die usage efficiency. It is beneficial to maintain high usage efficiency in order to lower costs; however, it is beneficial to maintain a large junction surface area in order to communicate more current. This creates a need to balance the demand to handle higher current loads with the increased cost of being able to accommodate fewer diodes on the die.
Traditional diodes have a two dimensional junction surface area. This design is not optimal to maximize the junction surface area while minimizing the area occupied by the diode on the surface of the die. What is needed is a more efficient diode.
One aspect of the embodiments disclosed herein is to improve over the state of the art.
Another aspect is to provide a three dimensional junction surface area which enables increased junction surface area relative to two dimensional junction diodes of similar size.
Another aspect is that with a greater junction surface area the rectifier is able to pass more current than a two dimensional structure of similar size.
Yet another aspect is that because of its ability to pass higher current levels, it can operate at a lower forward voltage which results in energy savings.
A further aspect is that because the junction surface area is increased without increasing the space occupied by the rectifier on the substrate surface, there is increased usage efficiency of the semiconductor substrate which results in cost savings.
One or more of these aspects will become apparent from the specification and claims that follow.